Gear-testing machine



J. L. MATTHEWS. GEAR TESTING MACHINE.

APPLICATION FILED DEC-27 i920.

Patented Oct. 18, 1921.

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UNITED STATES PATENT OFFICE.

JOSEPH L MATTHEWS, HIGHLAND PARK, JERSEY, ASSIGNOR TO` INTERNA- TIONAL MOTOR COMPANY, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE.

GEAR-TESTING MACHINE.

Specification of Letters Patent. Patented Oct. 18, 1921.

Application led December 27, 1920. SeriaLNb. l$33,128.

To aZZ whom z't may concern.'

Be it known that I, JOSEPH L. MATTHEWS, a citizen of the United States, residing in Highland Park, in the State of New Jersey, have invented certain new and useful Improvements in Gear-Testing Machines, of which the following is a specification, reference bein had to the accompanying drawing, forming a part hereof.

This invention relates to a type of gear testing machine in which blank disks of correct outline and properly centered are used in initially setting the indicator before theV one o1 two ears to be tested are placed in position. ore particularly, the invention is concerned with certain improvements in machines of this type whereby it is possible to increase the facility and speed of testing and Secure a very sensitive and exact indication of the accuracy of the teeth, the accuracy of the pitch diameter of the gear under test, aV correct indication of concentricity and, where a pair of gears is tested,

a proper determination of the spacing of their centers. Another object is concerned with the provision of a machine which shall be of simple construction and convenient to assemble and manipulate. These and other objects of the invention will appear in greaterdetail hereinafter in connection with the description of the embodiment illustrated inthe drawing, wherein- Figure 1 is a view in plan of the improved machine. Y'

Fig. 2 is a fragmentary viewjin side elevation thereof, parts being broken away to show the relation between the indicator head, the slide and the spring, pressed plungers carried with the head.

Fig. 3 is a view in transverse section taken on the plane indicated by the line 3--3 of Fig. l and lookingin the direction of the arrows.

Fig. 4i is a view in transverse section taken on the plane indicated by the line 4 4 of Fig. l and looking in the direction of the arrows.

Fig. 5 is a fragmentary sectional detail view showing the spring pressed plunger in dthe head' between the indicator, and the sli e.

The base of the machine a is formed with undercut ways` a in which are slidalxly mounted a slide b and an indicator head c.

At one end of the base a is supported xedly meshing are to be tested, this spur gear g is illustrative of one of them. On the shaft e may be secured removably a knurled retaining disk e which may secure the gear g in place and be used as a convenient hand hold for rotating the gear g with the disk f when desired.

On th-e slide is carried a bearing b in which is journaled a vertical shaft it on which is mounted a hardened circular master disk z' of the same diameter as the pitch dlameter of the gear to be tested. rl'he shaft a extends upwardly to receive removably a spur gear k to be tested. Extending transversely of the slide b and preferably alined with one another are slidable pins Z, Z"

formed at their outer ends with clamping clamping relation with the undercut ways a and lock the slid-e Z) against movement. The inner ends of the pins Z, Z are beveled and engaged by the tapered end of a clamping screw m on which is carried convenient hand wheel m to permit rotation of the screw m for the purpose of clamping and releasing the pieces Z2.

The -indicator head c has mounted longitudinally thereof a plurality of spring pressed plungers n, the ends of which protrude beyond the face of the head for engagement with the proximate end of the slide b. In the head c. is also mounted a spring pressed plunger 0 which extends through the head and has one end for en! gagement with' an ear b? on the slide b, and the other end for engagement with an actuating plunger 0 of an indicator p. The indicator fp is supported on a rod p2 which eX- tends into the head c and is clamped therein by means of'a set screw p3. Associated with the head c is a'suitable clamp shown as a loose plunger c which bears against the bottom wall of the channel formed by the walls a. vin the base a andds actuated; by a hand screw, indicated at c2. By manipulation "of the hand screw c2 the clamp c can `be forced against the base a so as to hold the head c against movement thereon.

The machine has such elements that gears of any ratio but of the same pitch can be 'tested with the same master gear and disk.

. and slide b are unclamped. rIhe slide b is 'determined spacing of the disks f, c'.

moved until the disk z' is at a predetermined distance from the disk f, this distance being determined by a feeler gage.` Clearance between the disks will depend on the permissible error in pitch diameters.I rlhe slide will be clamped with the disks z', f, so spaced. The head c will n ow be moved to bring the plunger o into engagement with the ear b2 thereby causing relative movement between the plunger and the head and consequent movement of the plunger p of the indicator p. For convenience, it will usually be de-` sirable to slide the head 0 until the index needle registers a distance equal to the prrehe head e will be clamped in position with the needle at such a setting. The slide b will then be unclamped by manipulation of the hand `wheel m. The spring pressed plunger m will immediately force the slide b to the left until the disks f, i bear against one another. The pinion k to be tested is then placed on the shaft lz, in mesh with the master gear'g. For gears having accurate pitch diameters equal to the diameters of the disks f, z', the indicator hand will remain stationary. When the gears are rotated, however, all irregularities in the teeth, lack of concentricity, and variation in centers will be sensitively and exactly indicated by oscillations of the pointer onA the index p. The tester can readily observe whether these variations exceed the predetermined permis- .sible error.` Where the initial setting has been made inthe manner described the permissible error in one direction would cause the hand to indicate Zero, while the permissible error in" the other direction would cause the hand to register twice the distance .l

Lacasse of its initial setting. Hav-ing the initial setting it is" evident that the head c need not be unclamped lduring a test run and that succeeding pinions lc can be readily placed on the shaft h. and removed therefrom after revolving the gears g, 7c.

I claim as my invention:

l. ln a gear testing machine, a base provided with ways, a'slide and an indicator head mounted reciprocably in said ways, means to clamp the slide and head in the ways, a relatively fixed vertical spindlel mounted on the base, a vertical spindle mounted on the slide, circular master disks mounted on the respective spindles, said spindles being adapted to receivel gears, an indicator vmounted on the indicator head, means toy operatively engage the indicator head with the slide, and meansv to press the slide along the Ways toward the said relatively ixed vertical spindle.

2. In a gear testing machine, a base provided with ways, a slide and an indicator `head reciprocable in said ways, a vertical spindle journaled in said base, a vertical spindle journaled liii said slide, coperating circular Amaster disks carried on said spindles, said spindles being adapted to receive intermeshinggears, an indicator carried with the head, a spring pressed connection between the indicator head and the slide, spring pressed plungers carried with the head and engaging the proximate edge of the slide, and means to clamp the head and^ the slide in the ways.

3. In a gear testing machine, in combination with a base provided with ways, a vertical spindle carried with the base to support a gear, a slide mounted reciprocably in said ways and having a vertical fspindle' to carry a gear for meshing with said iirst named gear, oppositely extending clamping pieces mounted transversely of said sllde and having their outer ends in engagement with said Ways and having their inner ends beveled, and a hand screw to engage said beveled ends to force the members in clamping engagement-J with th ways.

This specification signed this 20th day of December, A. D. 1920. A

JosEPi-i L. MATTHEWS. 

